Comparing Fractions
Part of the Factors & Fractions section of Coddy's Pre-Algebra journey. Lesson 26 of 58.
When two fractions have the same denominator, their pieces are the same size, so the one with more pieces is bigger: 7/9 > 5/9. Compare the tops and you are done.
Different denominators need a common one first. Compare 2/3 and 3/5: rename both over 15, as you did at the start of this chapter. 2/3 is 10/15 and 3/5 is 9/15. Now the pieces match, and 10 fifteenths beat 9, so 2/3 > 3/5.
A shortcut does the same job: cross products. Multiply each top by the other fraction's bottom: 2 × 5 is 10 and 3 × 3 is 9. These are exactly the new tops over 15, so the fraction whose top gave the bigger product is the bigger fraction.
Challenge
Which sign goes between 3/4 and 5/7: less than, equal to, or greater than? Pick it in the box.
Try it yourself
Pick the right answer
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Factors & Fractions
1Factors and Multiples
What a Factor IsFactor PairsDivisibility RulesMultiplesPrime or CompositeRecap: Factors and Multiples4What a Fraction Is
Parts of a WholeFractions on the LineA Fraction of a NumberImproper FractionsRecap: What a Fraction Is7Multiplying Fractions
Top Times TopCancel FirstWhole Times FractionA Fraction of a FractionRecap: Multiplying Fractions10Fractions in Stories
Part of a GroupWhat Is LeftSharing a FractionScaling a RecipeRecap: Fraction Stories2Prime Factorization
Factor TreesUsing ExponentsOne Tree per NumberBigger NumbersRecap: Prime Factorization5Equivalent Fractions
Same Amount, New NameSimplifying FractionsSimplify in StepsComparing FractionsRecap: Equivalent Fractions